The invention relates to a method for controlling a gear change in the case of a non-synchronized dog-shift transmission, in particular for motorcycles.
For example, production motorcycles from the Applicant are equipped with a non-synchronized dog-shift transmission. Shift transmissions of this type have a selector drum for carrying out the shift operations. Here, shift forks are provided with in each case one pin which protrudes in each case into a groove of the selector drum. Depending on the contour of the respective groove, a rotation of the selector drum brings about the shift operation by way of displacement of a shift fork on the selector rod. The grooves on the selector drum are arranged in such a way that its rotation causes a displacement of the shift forks such that gears of the transmission are shifted sequentially.
Reference is made, for example, to EP 1 256 743 B1 or DE 10 2011 088 352 A1 with respect to mechanical details of a non-synchronized dog-shift transmission of this type.
It is an object of the invention to improve dog-shift transmissions of this type with regard to their reliability.
According to the invention, this and other objects are achieved by a method for controlling a gear change in the case of a non-synchronized dog-shift transmission having at least one shift (selector) fork which can be controlled via a selector drum. The rotational position of the selector drum is detected by way of a position sensor on the selector drum and is transmitted to an electronic control unit for controlling a drive engine. By use of the detected rotational position, the control unit recognizes whether the/a shift fork is situated in an intermediate position, in which neither of the two possible gears which are assigned to it is engaged. If the shift fork is in the intermediate position, the rotational speed of the drive engine is regulated to a mean value between the target rotational speeds of the two possible gears when the clutch between the drive engine and the dog-shift transmission is additionally open.
The invention also comprises a control apparatus and an electronic control unit for carrying out the method according to the invention.
The invention is based on the following considerations.
In the case of non-synchronized dog-shift transmissions, high demands are made, in particular, of the component strength of the mechanical components, in particular of the respective groove in the selector drum when a gear change is carried out. It has been determined in tests that possible resonance vibrations are prevented by way of the rotational speed interventions according to the invention and, as a result, the service life of the selector drum can be extended.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.